New player looking for some champion selection

Hi there, just got into this game not too long ago, and looking for some champion ideas.

I know there are plenty of threads around with these kind of topic but with all the patches it's hard to find information that's 100% relevant. I would like to main top, jungle, support.

Here are my thoughts on what champions would suit me best at my low skill level:

• Something with burst damage, a get in get out champion, as my skills are low, I am likely to get harassed in lanes and out traded by other players, I figure the best kind for me would be the get in and get out types? but yet not too squishy. My reasoning is that at new level, I wont even know what champion out trades what with given gears / level. And it'd be best if I can just jump in and out against sustain champions, and against another burst champion it will most likely be a skill matchup.
• Late game champions, because if my skills are low, the chance of me helping to finish off the game would be fairly low, I should focus my time on developing champion for late game.

So in this instance, I think the champions I've been using wont suit me that well ie: Garen, Jax, Kayle, warwick.

Are my thoughts valid for a beginner? and can anyone suggest champions that I might be able to do well in? thanks